A comprehensive water-energy-carbon (WEC) nexus model for an urban water system (UWS) using system dynamics is proposed to assist municipalities, urban developers, and policy makers for neighborhood water planning and management. The proposed model and decision support tool was developed for the operational phase of UWSs. The model was validated using historical water and energy consumption data (2005–2014) of Penticton (British Columbia, Canada). Spearman’s correlation coefficients between water and energy, water and carbon, and energy and carbon were 0.94, 0.89, and 0.83, respectively, revealing highly significant interconnections. The energy for water was , water for energy was , and carbon emissions were from energy use and from wastewater processes. A Monte Carlo–based sensitivity analysis showed residential outdoor irrigation and water heating energy for showers and dishwashers have higher contribution to model variability. The intervention analysis reveals significant differences in savings in water, energy, and carbon for various water and energy-based interventions in UWSs and the developed tool is well capable for analyzing these dynamic savings.
The construction industry is continuously searching for sustainable materials to combat the rapid depletion of global resources and ongoing ecological crises. Biocomposites have recently received global attention in various industries due to their renewability, low cost, and biodegradability. Biocomposites’ potential as a sustainable substitute in construction can be understood by identifying their diverse applications. Moreover, examining their life cycle environmental and economic impacts is important. Therefore, this study is a novel attempt to encompass biocomposites’ construction applications and their environmental life cycle performance. Statistical analysis is done related to the temporal distribution of papers, publishers, literature type and regions of studies. First, this paper reviews the latest research on the applications of natural fiber biocomposites in construction with their key findings. The applications include fiber reinforcements in concrete, external strengthening elements, internally filled hollow tubes, wood replacement boards, insulation, and non-structural members. The second part covers the life cycle assessment (LCA) and cost studies on biocomposites. The life cycle studies are currently rare and require more case-specific assessments; however, they highlight the benefits of biocomposites in cost savings and environmental protection. Finally, this study provides key suggestions for increasing the applicability of biocomposites as sustainable construction materials.
Identification of drought is essential for many environmental and agricultural applications. To further understand drought, this study presented spatial and temporal variations of drought based on satellite derived Vegetation Condition Index (VCI) on annual (Jan–Dec), seasonal monsoon (Jun–Nov) and pre-monsoon (Mar–May) scales from 1982–2015 in Nepal. The Vegetation Condition Index (VCI) obtained from NOAA, AVHRR (National Oceanic and Atmospheric Administration, Advanced Very High Resolution Radiometer) and climate data from meteorological stations were used. VCI was used to grade the drought, and the Mann–Kendall test and linear trend analysis were conducted to examine drought trends and the Pearson correlation between VCI and climatic factors (i.e., temperature and precipitation) was also acquired. The results identified that severe drought was identified in 1982, 1984, 1985 and 2000 on all time scales. However, VCI has increased at the rate of 1.14 yr−1 (p = 0.04), 1.31 yr−1 (p = 0.03) and 0.77 yr−1 (p = 0.77) on the annual, seasonal monsoon and pre-monsoon scales, respectively. These increased VCIs indicated decreases in drought. However, spatially, increased trends of drought were also found in some regions in Nepal. For instance, northern areas mainly in the Trans-Himalayan regions identified severe drought. The foothills and the lowlands of Terai (southern Nepal) experienced normal VCI, i.e., no drought. Similarly, the Anomaly Vegetation Condition Index (AVCI) was mostly negative before 2000 which indicated deficient soil moisture. The exceedance probability analysis results on the annual time scale showed that there was a 20% chance of occurring severe drought (VCI ≤ 35%) and a 35% chance of occurring normal drought (35% ≤ VCI ≤ 50%) in Nepal. Drought was also linked with climates in which temperature on the annual and seasonal monsoon scales was significant and positively correlated with VCI. Drought occurrence and trends in Nepal need to be further studied for comprehensive information and understanding.
1 February 2019 in Science of The Total Environment
Hydrogen-based transportation has gained popularity and has presented significant growth over the past few years, providing an excellent platform for capitalizing on natural resources while attaining global carbon policies and sustainability targets. However, lack of infrastructure, cost of fuel cell vehicles and hydrogen fuel, and absence of established hydrogen supply chains have been identified as critical challenges of hydrogen-based mobility. Despite current studies predominantly focusing on hydrogen-fueled passenger vehicles and related infrastructure, it was identified that the impacts of hydrogen fuel supply chain for freight transportation from a life cycle thinking perspective have been largely overlooked. This article aims at critically reviewing the existing body-of-knowledge on the current status of hydrogen fueling supply chain and exploring the potential of integrating hydrogen fuel for road freight transportation. Accordingly, the current status of alternative fuel use for freight transportation is discussed over technical, economic, and environmental dimensions outlining its benefits and challenges. Moreover, the pertinence of innovative and established methods of hydrogen production, distribution, and storage for freight transportation are evaluated based on a comprehensive literature review. This study reveals that the transformation of freight transportation into low-emission alternative fuels would require a comprehensive multicriteria assessment that includes technical, economic, environmental, and social feasibilities over the life cycle of the freight vehicle and the fuel supply chain. Moreover, decision parameters affecting the optimal fuel selection process were established through this study, while providing insights on the future prospects for hydrogen-fueled freight transformation in Canada.